# chem

posted by .

The mass of the CuSO4 x 5H2O sample is 1.664 g. The mass of the recovered copper is 1.198 g.
Calculate the percent copper in pure copper sulfate pentahydrate(this is the theoretical percent copper). One mole of copper has a mass of 63.55 g, and by addition, one mole of CuSO4 x 5H2O has a mass of 249.5 g.

• chem -

So what's the question? Percent Cu in the sample?
(1.198/1.664)*100 = ??

Theoretical yield =
(mass Cu/mass hydrate)*100 = (63.55/249.5)*100 = ??

• chem -

The question is asking for percent of copper in the sample( so the first step shown above), but when I had to calculate the experimental percent I did the same thing, and i got 72%( is that the correct number of significant figures)?

I also wanted to know when I have to calculate the error of the % of copper what number do I use as true value and actual value?

• chem -

The mass of the CuSO4 x 5H2O sample is 1.664 g. The mass of the recovered copper is 1.198 g.

1. Compute the experimental percent by mass of copper in the sample:
1.1664/1.998x 100=71.81%

2. Calculate the percent copper in pure copper sulfate pentahydrate(this is the theoretical percent copper). One mole of copper has a mass of 63.55 g, and by addition, one mole of CuSO4 x 5H2O has a mass of 249.5 g:

63.55/249.5x100= 25.47%

3. In order to calculate the error of the % Cu and the percent error of the % Cu I know I am suppose to use 1.198 as the experimental value, but I am not sure what to use for the true value.

• chem -

## Similar Questions

1. ### chem

The mass of the CuSO4 x 5H2O sample is 1.664 g. The mass of the recovered copper is 1.198 g. 1. Compute the experimental percent by mass of copper in the sample: 1.1664/1.998x 100=71.81% 2. Calculate the percent copper in pure copper …
2. ### chemistry.

A student was asked to make some copper(II) sulfate-5-5 (CuSO4.5(H2O) BY reacting copper(II) oxide (CuO) with sulfuric acid. a) Calculate the molar mass of the copper (II) sulfate-5-water which is (64+32+64) + (10+80)=250 mol b)Calculate …
3. ### Chemistry

A 2.50 gram sample of bronze was dissolved in sulfuric acid. The copper in the sample reacted with sulfuric acid to form copper sulfate. Cu (s) +2 H2SO4 (aq) -> CuSO4 (aq) +2 H2O (l) The copper sulfate formed in this reaction was …
4. ### Chemistry

calculate the mass percent of sand, sodium chloride and copper(ll) sulfate in a sample that yields: mass of sample= 14.088g, mass of sand=0.2255g, mass of copper(ll)oxide = 0.1994g (assume 100% yield for each of the copper(ll) reactions) …
5. ### Science

Calculate the mass percent of sand, sodium chloride and copper (II) sulfate in a sample which yields the following data: mass of sample = 1.088g, mass of sand = 0.2255g, mass of copper (II) oxide = 0.1994g (assume 100% yield for each …
6. ### chemistry

heating copper sulfate pentahydrate will evaporate the water from the crystals. leaving anhydrous copper sulfate,. a white powder. what mass of anhydrous CuSO4 would be produced by heating 500.0g of CuSO4*5H2O